Centrifugal fan



0d. 13, 1953 SCHLUMBOHM 2,655,310

CENTRIFUGAL FAN Filed Aug. 1, 1952 2 Sheets-Sheet l Hlll HI ill lllllllll z\\ INVENTOR.

Oct. 13, 1953 Filed Aug. 1, 1952 P. SCHLUMBOHM CENTRIFUGAL FAN vlA.-

2 Sheets-Sheet 2 INVENTOR.

Patented Oct. 13, 1953 Es PM oer Peter Schlumbohm, NeW-:York',-:N.' riilication'l fiik t 1i 2,}S.Lfial No. 2.213%

i -olaimsr (o1. zao rzsay present in'vention refers to a"method-"and to apparatus for umping fluids by centrifugal force.v The invention; is"; illustrated by way of examples in Figure 1 to Figure 8 of the accompanyingdrawings: In-order to explain the apparatus shownin the drawings, it is first necessary to explain the"meth'ocl and the new physical principle involved.

Mini invention is based-on the obs'ervation that a. rotating di'sd comprisingin itswall tubular channels arranged coaxially with 1 the driving? shaft of tl'1e disc will pump fiuids centri'fu'gally, if one provides a one direction-flow through said tubular channels. The effect in that case is that of a stonje'ina sling. The-fiiiidduring its transitoi'y stay'witliim'those tubular channels acquires the centrifugal momentum from the rotating disc. Among the possibilities of producin onedirection flow, I found that the simplest method to this effect is to have the rotating disc, which I will call the centrifuging wall, rotate near a wall which I will call the co-pumping wall. Concerning this method, three modifications are shown in the drawings, as follows:

Figure 1 shows the centrifugal wall I in cooperation with a non-rotating co-pumping wall 4.

Figure 2 shows the same centrifuging wall and a co-pumping wall 5 arranged on the same shaft. In this modification the co-pumping wall rotates but is not itself a centrifuging wall.

Figures 3 and 4 illustrate the third modification. The centrifuging wall I and the co-pumping wall E are arranged on the same shaft. In this modification the co-pumping wall 6 is also a centrifugin wall. Figure 4 shows a variation of Figure 3. Due to the identity of the structure of wall I and wall 6 of Figure 3, these walls form in Figure 4 one single body with a gap 8 separating the two centrifuging and co-pumping elements l and 6'.

Figure 5 shows a strip 9 of corrugated material comprising the non-undulated Wall II and the undulated wall ID. This material can serve, as shown in Figure 6, to build up a centrifuging wall I, as shown in Figures 1 to 4.

Figure 7 is a structural variety of the modification shown in Figure 2. In this case the copumping wall 5' is arranged between the centrifuging wall I and the motor 3.

Figure 8 is a perspective side view of Figure 7 showing a honeycomb structure of the centrifuging wall I". Such structure allows for plastic or metal construction of the centrifuging wall, combining thin walls with maximum tensile strength of the rotating disc. Metals or plastics as mate- The pumping effect' 'is indicated by the farrotvsf m r ies-ire; 1; Figure-=2 ana rrgurem" The fiuid enters coaxially intethe-tubul-ar channels of thefcentrifuging wall and is then deflected radially between the centrifuging wall and the co-pumping wall. In Figure 3 and Figure 4 the arrows indicate the flow of the fluid coaxially through the centrifuging and co-pumping walls and a radial deflection in the gap between them.

I stated that a special inventive step is to provide tubular flow channels. Perforations, meaning holes, in a wall would not do. As a definition, it may be helpful to say that a perforation becomes a tube when the length of the channel is larger than its diameter. However, even such a minimum length tube would not be effective for the present invention. I found that the ratio between diameter and length must be a multiple of the diameter. One can experimentally show clearly how a ratio of 4:1 has a much better pumping effect than a ratio of 2:1, and that a ratio of 10:1 is still better than a ratio of 7:1.

The wall shown in Figure 6 illustrates a rotor actually built by using a 1" wide strip of the material shown in Figure 5, which has ten channels per inch. In that case, a diameter of for the tubular channel and a length of 1" for that tubular channel, represents a ratio of 1:10.

The honeycomb wall shown in Figure 8 is, for reasons of clarity, drawn in a larger scale than would be used for a construction drawing. The honeycomb would actually have the fine structure of the arrangement of Figure 6.

The optimum ratio between length and diameter varies with the viscosity of the fluids to be pumped, with the various R. P. M. of the driving shaft, and with the distance between the centrifuging wall and the co-pumping wall.

The leading principle is to convey to the fluid centrifugal momentum during the fleeting moment of its passage through said tube.

In my experiments I have built a blower of 3 surprisin efiiciency by building the arrangement as shown in Figure 3 with a diameter of 15" for walls and 6 and rotating them at 1750 R. P. M. Both walls I and 6 were built as indicated in Figures 5 and 6.

In winding the strips as illustrated in Figure 5 I applied rubber cement to the base layer ll so that it would be glued to the layer ll! of the preceding turn.

The described blower was sufficient for the purpose of blowing air.

Having now described the nature of my invention and having shown by way of example the manner in which it may be performed, I claim as my invention:

1. A centrifugal fan comprising a rotatable member with a center arbor for a driving shaft, said member comprising a disc of reticulated structure consisting of a multitude of tubular flow channels passing from one side of the disc a to the other side and being open at both ends, said channels being parallel to the axis of rotation of said member, said fan structure further comprising a co-pumping wall equi-distantly spaced from the open ends of said tubular channels at one side of said disc, and the space between the disc and the co-pumping wall being free of obstructions from the radially innermost tubular channels to the outer periphery of the disc.

2. A centrifugal fan comprising a rotatable member with a center arbor for a driving shaft, said member comprising a disc of reticulated structure consisting of a multitude of tubular flow channels passing from one side of the disc to the other side and being open at both ends,

said channels being parallel to the axis of rotation of said member, said fan structure further comprising a rotatable co-pumping wall equidistantly spaced from the open ends of said tubular channels at one side of said disc, and the space between the disc and the co-pumping wall being free of obstructions from the radially innermost tubular channels to the outer periphery of the disc.

3. A centrifugal fan as claimed in claim 1 in which the co-pumping wall comprises a rotatable member with a center arbor for a driving shaft, said member comprising a disc of reticulated structure consisting of a multitude of tubular flow channels passing from one side of the disc to the other side and being open at both ends, said channels being parallel to the axis of rotation of said member. 4. A centrifugal fan as claimed in claim 2, in which said rotatable member and said co-pumping wall are made of one integral piece of material, mounted on a common center arbor.

PETER SCI-ILUMBOHM.

References Cited in the file of this patent UNITED STATES PATENTS 

